The International Federation for Human Rights (FIDH) and the Iranian League for the Defence of Human Rights (LDDHI) have issued a joint statement warning that the “disappearance” of Iran’s opposition leader would have consequences.

The two rights groups indicate they are taking measures to file a complaint with the United Nations Working Group on Enforced or Involuntary Disappearances (UNWSEID) on behalf of MirHosein Mousavi, Mehdi Karroubi and their spouses Zahra Rahnavard and Fatemeh Karroubi.

Despite announcements by both the Iran and Tehran prosecutors that the opposition leaders are still in their homes under house arrest, the two rights groups note that the children of the two couples say their parents have been in an unknown location since February 28.

The joint statement cites unofficial reports that the two couples have been moved to a prison under the supervision of the Islamic Revolutionary Guards.

The opposition leaders had been put under house arrest after they called for a march on February 14 in support of the recent Arab uprisings.

Their children have issued a statement saying that all evidence suggests their parents are no longer at their homes.

“The houses of the four opposition leaders have been surrounded by the security forces and all their contacts were under scrutiny for months,” said Karim Lahidji, vice-president of FIDH and president of the Iranian League for the Defence of Human Rights. “Now they have disappeared. Their case constitutes a clear application of enforced or involuntary disappearance. The Iranian authorities are responsible for their safety. We will alert and file a complaint with the UN Working Group on Enforced or Involuntary Disappearances on their behalf.”

The statement notes that on March 1, hundreds of thousands of people demonstrated in Tehran and other major cities to end repression and demand the release of the opposition leaders. But they were faced with extreme violence from government forces.

Lahidji states that in view of the “ongoing brutal suppression of peaceful protesters and the disappearances in the Islamic Republic”, the international community should pass a resolution which includes the appointment of a special rapporteur on human rights for Iran.

He also calls on the European Union to take action on the list of human rights violators the rights group has submitted to them in February 2011 by “freezing their assets and imposing visa bans, and reiterating its ban on visits by European officials to Iran.”